title: Apoptosis of human cholangiocarcinoma cell lines induced by β-escin through mitochondrial caspase-dependent pathway.
abstract: The study aimed to evaluate the effects of β-escin on human cholangiocarcinoma cell lines (QBC939, Sk-ChA-1 and MZ-ChA-1) and to explore its mechanisms. Cell growth, cell cycle and apoptosis were investigated, respectively, by MTT assay, single PI and FITC/PI double-staining flow cytometry, and fluorescence microscopy. The protein expression was determined by western blotting. The study revealed that β-escin inhibited cholangiocarcinoma cell growth in a dose- and time-dependent manner, and the cell cycle of QBC939 and Sk-ChA-1 cells was arrested in the G2/M phase, and MZ-ChA-1 cells in G1 phase. Apoptosis of the three cholangiocarcinoma cell lines induced by β-escin was associated with the collapse of the mitochondrial membrane potential and the activation of caspase-3. The apoptotic effect of β-escin was suppressed by pancaspase inhibitor z-VAD-fmk. Molecular dissection revealed that the antiapoptotic protein bcl-2 was down-regulated after cholangiocarcinoma cell lines were treated with β-escin, while the protein levels of bax and p53 were unchanged. Apoptosis was accompanied by an increase in reactive oxygen species (ROS). These results suggest that β-escin induces apoptosis of cholangiocarcinoma cells through an intrinsic mitochondrial caspase-dependent pathway, and the increase in the bax/bcl-2 ratio and ROS may play important roles in β-escin-induced apoptosis of cholangiocarcinoma cells.
authors.affiliation: Key Laboratory of Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen, China.
authors.forename: Dong-Yan
authors.initials: DY
authors.lastname: Shen
authors.forename: Jin-He
authors.initials: JH
authors.lastname: Kang
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.forename: Wen-Qing
authors.initials: WQ
authors.lastname: Zhang
authors.forename: Wen-Gang
authors.initials: WG
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhao
authors.forename: Qing-Xi
authors.initials: QX
authors.lastname: Chen
mesh_terms: D031319:Aesculus / Q000737:chemistry*; D000590:Amino Acid Chloromethyl Ketones / Q000378:metabolism; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects*; D001650:Bile Duct Neoplasms / Q000378:metabolism / Q000517:prevention & control*; D001653:Bile Ducts, Intrahepatic / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D053148:Caspase 3 / Q000378:metabolism; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D018281:Cholangiocarcinoma / Q000378:metabolism / Q000517:prevention & control*; D004268:DNA-Binding Proteins / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D004928:Escin / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects; D009687:Nuclear Proteins / Q000378:metabolism; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D000072160:Tumor Protein p73; D025521:Tumor Suppressor Proteins / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D000590:Amino Acid Chloromethyl Ketones; D000972:Antineoplastic Agents, Phytogenic; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D010936:Plant Extracts; D019253:Proto-Oncogene Proteins c-bcl-2; D017382:Reactive Oxygen Species; D000072160:Tumor Protein p73; D025521:Tumor Suppressor Proteins; D051028:bcl-2-Associated X Protein; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D004928:Escin; D053148:Caspase 3